London’s new Muslim mayor, Sadiq Khan, accused Prime Minister David Cameron late Saturday of using “Donald Trump playbook” tactics to try to divide communities in a bid to prevent his election.

Speaking after he was sworn in with a promise to be “mayor for all Londoners”, the Labour lawmaker condemned Cameron’s Conservatives for trying to link him to Islamic extremists during the election campaign.

“They used fear and innuendo to try to turn different ethnic and religious groups against each other — something straight out of the Donald Trump playbook,” Khan wrote in The Observer newspaper.

“Londoners deserved better and I hope it’s something the Conservative party will never try to repeat,” he added.

Khan won 57 percent of the vote in Thursday’s mayoral election, securing 1.3 million votes to see off multimillionaire Tory Zac Goldsmith and making history as the first Muslim mayor of a major Western capital.

The 45-year-old, the son of a Pakistani immigrant bus driver, hailed his victory as a triumph of “unity over division” after weeks of Tory criticism over his past appearances at public events alongside radical Muslims.

A number of Conservative politicians criticized the tone of the campaign, but Defense Secretary Michael Fallon said the questions raised had been legitimate.

Khan had admitted representing some “pretty unsavory characters” during his previous job as a human rights lawyer but said their views were “abhorrent”.

“Both candidates were asked questions about their backgrounds, their personalities, their judgment, the people they associate with,” Fallon told BBC radio.

“That’s the nature of our democracy and the rough-and-tumble of politics.”

Khan’s win was decisive enough to stave off calls for an investigation, following reports that some polling places, particularly in areas with large Jewish populations, suffered from unexplained “errors” preventing voters from casting their ballots.

He broke from convention by taking his oath of office in a multi-faith ceremony at Southwark Cathedral, promising to represent “every single community, and every single part of our city, as mayor for all Londoners”.

His success, however, is deemed to be a boost for Labour leader Jeremy Corbyn who has been battling a row over anti-Semitism and growing criticism from the moderate wing of his party since his election in September.

Last month, Khan himself criticized the anti-Semitism within his own party, saying the Labour party’s failure to tackle anti-Jewish sentiment was “unacceptable”

“I said from the outset, I’m embarrassed, I’m sorrowful about anti-Semitism in my party,” he added. “I think the Labour leadership could have taken a tougher stance—and should have taken a tougher stance.”

Corbyn was conspicuously absent from Khan’s signing-in ceremony and in his article, the new mayor appeared to criticize the way Labour was being run.

The party “only wins when we face outwards… and engage with all voters”, Khan wrote, adding, “It’s crucial for the whole country that the Labour party becomes a credible government-in-waiting.”

AFP contributed to this report.